title: Comparative study of TGF-alpha and P53 markers' expression in odontogenic keratocyst and orthokeratinaized odontogenic cyst.
abstract: BACKGROUND
  Odontogenic keratocyst (OKC) is an aggressive cyst and its recurrence is higher than other odontogenic cysts, orthokeratinized odontogenic cyst (OOC) is a cyst with moderate biological behavior in comparison with OKC, but with the probability of carcinomatous changes. The present study aims to evaluate the quantity and intensity of the expression of P53 protein and transforming growth factor alpha (TGF-alpha) in OKC and OOC in order to compare the biologic behavior of these two cysts.
  
  
  METHODS
  This is a cross-sectional study. The samples include 30 cysts (15 OKC and 15 OOC), all stained immunohistochemically for P53 protein and TGF-alpha by the Novolinke polymer method. Then, all the cases were examined with an optical microscope with Χ400 magnification and the stained cells were counted in the basal and parabasal layers. Finally the results were analyzed by the Mann-and Wilcoxon tests (P value < 0.05).
  
  
  RESULTS
  The difference between the expression of P53 protein in the basal layer in OKC and OOC was not statistically significant (P value = 0.076). The difference between the expression of P53 protein in the parabasal layer in OKC and OOC was statistically significant (P value = 0.003); moreover, the difference between the expression of TGF-alpha in the basal layer in OKC and OOC was not statistically significant (P value = 0.284). The difference between the expression of TGF-alpha in the parabasal layer in OKC and OOC was statistically significant (P value = 0.015).
  
  
  CONCLUSIONS
  Since there was a higher expression of P53 protein and TGF-alpha in OKC compared to those in OOC, the probability of carcinomatous changes was at least theoretically higher in OKC than in OOC.
authors.affiliation: Torabinejad Dental Research Center and Department of Oral and Maxillofacial Pathology, School of Dentistry, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Parviz
authors.initials: P
authors.lastname: Deyhimi
authors.forename: Zahra
authors.initials: Z
authors.lastname: Hashemzade
keywords: Odontogenic cysts; P53 protein; TGF-alpha